Corner metal lath



Jan. 31, 1956 w. M. RlEs CORNER METAL LATH 2 Sheets-Sheet 2 Filed April l5, 1949 mi lNvl-:NToR

Will/'am M. Rie s United States Patent O l CORNER METAL LATH William M. Ries, Beech Bottom, W. Va., assignor to Wheeling Steel Corporation, Wheeling, W. Va., a corporation of Delaware Application April 15, 1949, Serial No. 87,600

4 Claims. (Cl. 72-1'21) This invention relates to corner metal lath and more particularly to corner metal lath adapted for use in an inside corner. v

Inside corner metal lath has in the past been fabricated from expanded metal either by slitting larger sheets of metal wall lath into pieces of proper width and bending them to the approximate contour of an inside corner or by bending narrow sheets of metal lath made especially for bending into corner lath. Corner metal lath fabricated in either of these ways has not proven entirely satisfactory. Frequently the apex of the corner angle of such metal lath is not equally distant from the edges ofthe bent over portions or wings of the lath. This means that the corner is not always in the center of the corner metal lath, one wing often being longer than the other. At times the apex of the corner is not only not equidistant from the edges of the wings but is also not parallel to either edge. There is therefore no symmetry in the corner lath and the actual apex line ot' the corner is undened and difficult to follow. Since there is no well-defined corner line it is ditiicult to place the lath properly in an inside corner and it is also diicult to plaster over the lath with the formation of a perfectly straight, well-defined corner. These characteristics lead to considerable eyestrain and fatigue in the workmen who are installing the lath and plastering over it as well as to mechanical diiiiculties in getting the plaster to properly key behind the lath and yet maintain suicient plaster above the lath to prevent its bleeding through the surface of the plaster. Bleeding through the plaster is caused by the passage of oxides from the metal lath to the surface of the plaster when the lath is not sufliciently buried in the plaster. This condition frequently occurs in inside corners where the lath is rounded across the apex of the corner due to the inability of the lather to get the metal corner lath properly into the apex of the corner. Moreover, lath of this type, since it does not have a rigid well-defined corner member, does not withstand handling satisfactorily and frequently is bent or distorted.

I have invented a corner metal lath which avoids these diiculties. My lath may comprise a center or cornerdefining member having an undulate conliguration and a pair of expanded metal wings extending angularly outwardly from said center member. Preferably the center member is of substantially greater width than the strands which form the expanded metal wings and the crests of its undulate configuration extend above and below a line formed by the intersection of the two general planes in which the wings lie.

The center member of the corner metal lath desirably maintains a stiff rigid corner line which is always centered in the apex of the corner and always well-defined. A center member of this type reduces eyestrain and fatigue and gives strength to the corner at the apex.

My corner lath also has other advantages. The undulate configuration of the center member provides pockets in the apex of the corner into which the plaster may be forced so as to lock the plaster behind the center member.

2,732,707 Patented Jan. 31, 1956 ICC Vthe line formed by the intersection of the two general planes in which the wings lie, a slight bowing in the wings results when the edges of the wings are fastened tightly to the wall surface. This bowing of the wings formsa pocket on either side of the center member between the wall lath and the wings into which plaster may be forced to key it more tightly to the corner lath. This bowing elect is especially important where the corner metal lath is used in conjunction with sheet lath where there are few openings into which the plaster can flow.

In the accompanying drawings illustrating a presently preferred embodiment of my invention,

Figure l is a perspective view of a section of corner metal lath according to my invention;

Figure 2 is a section on the line II-II of Figure 1;

Figure 3 is a section through a wall corner showing the application of corner lath; and

Figure 4 is a perspective view partly cut away of an inside room corner after plastering.

Referring irst to Figure l, I have illustrated a corner metal lath having a center or corner-defining member 10 of undulate configuration having alternately raised and depressed portions 11 and 11a. A pair of expanded metal wings 12 extend outwardly from the center member 10, the angle between the wings being about The pattern formed by the alternately raised and depressed portions 11 and 11a of the center member corresponds in general to the pattern of raised and depressed portions 13 and 13a of the strands 14 forming the expanded metal wings. The center member 10 is of substantially greater width than any of the strands 14 of the expanded metal wings.

As a result of the undulate configuration and the greater width of the center member 10 the corner line of the corner metal lath is well-defined and is substantially more rigid than the wings of the lath.

In constructing a wall in which the metal corner lath of my invention is used, the metal corner lath may be applied to the wall by any of the well-known methods such as for example, by wiring it to metal lath or nailing it to wooden lath, sheet lath or wallboard. Such a wall may be constructed as shown in Figure 3 wherein I have illustrated a plastered wall corner having sheet lath 15 attached to the wall studding 16 to form a corner apex 17. The metal corner lath 18 is held in position in the corner by nails 19 which pass through the two wings of the lath adjacent their edges 20 into the sheet lath of the wall. When applied to the corner in this manner, the center member 10 will bridge the apex 17 of the corner of the wall leaving a void 21 between the apex of the corner and the center member, particularly behind the depressed portions 11a, into which plaster will flow to lock the corner. The wings 12 may be slightly bowed (see Figure 3) to form a pocket 22 on either side of the apex of the corner into which plaster 23 will flow to bond the corner thoroughly. The keying etlect thus attained contributes importantly to the production of clean, sound plaster corners, free from the tendency to crack and bleed.

The corner-defining property of the corner lath of my invention is more clearly illustra-ted by Figure 4 which shows a corner of a room which has been lathed with sheet lath 15 and to which the corner lath 18 of my invention has been applied. In such a wall construction the sheet lath is fastened to the s-tudding 16 of the wall and the corner lath 18 is fastened to the sheet lath by nails 19 which pass through the two wings 12 adjacent their edges 20. The corner-defining member 10 then forms a clearly deiined line 30 along the apex of the corner as is clearly illustrated in the drawings. Such a well-defined line is particularly important in reducing eyestrain and fatigue and in promoting straight and true corners in interiors where the lighting is poor.

While I have illustrated and described a presently prefllqdembodiment of my invention it is to be understood that the invention is not limited thereto but may be otherwise variously embodied within the scope of the following claims.

I claim:

1. A corner metalV lath comprising a corner-delining center member and a pair of expanded metal wings extending angularly outwardly from the center member substantially at right angles to each other, the center member having alternately raised and depressed portions corresponding to the pattern of raised and depressed portions of the strands forming the expanded metal wings, the raised portions of the center member being suiciently high to extend beyond a line forming the apex of the angle between the planes in which the wings lie.

2. A corner metal lath comprising a corner delining center member and a pair of expanded metal wings extending angularly outwardly from the center member substantially at right angles to each other, the center member having an undulate coniguration with crests alternately on opposite sides of a line formed by the intersection of the two planes in which the wings lie.

3. A corner metal lath comprising a corner defining center member and a pair of expanded metal wings extending angularly outwardly from the center member sub- ,stantiallyat right angles `to each other, the center member having an undulate configuration with crests alternately on opposite sides of a line formed by the intersection of the two planes in which the wings lie, the center member being of substantially greater width than the strands of the expanded metal wings.

4. A corner metal lath comprising a corner defining center member and a pair of substantially symmetrical expanded metal wings extending angularly outwardly from the center member in separate planes forming an angle of about 90 with each other, the center member having an undulate configuration with crests alternately on opposite sides of a line formed by the intersection of the two planes in which the wings lie.

References Cited inthe tile of this patent UNITED STATES PATENTS 1,104,475 Clark July 21, 1914 1,346,437 Albinson July 13, 1920 1,419,232 Curtis June 13, 1922 1,420,040 Jones June 20, 1922 1,619,401 Campbell Mar. 1, 1927 1,908,166 Moore May 9, 1933 

